What would you change in Heroes of Might and Magic IV?

What does it mean to have unnecessary spells? There are practically none here. In any given situation, each spell can be useful. And the fact that one is better and another is worse is only revealed through comparison. Take, for example, such a powerful spell as hypnosis, and cast it on dracogolems, bone dragons, or Black Dragons. And what will happen – will it be an unnecessary spell? But if you have a full spellbook, and you only manage to cast 2-3 spells, and then enemies approach and defeat you. Does that mean you wasted time collecting so much useless stuff that you couldn't use? Or maybe you're just to blame for not choosing the right spells to cast?